A Plan for Observation of the Antarctic Ozone Hole in 1991 under the Polar Patrol Balloon (PPB) Project
Hiroshi KANZA WA 1 and Yutaka K0Noo2
ボ ー ラ ー ・ バ ト ロ ー ル ・ バ ル ー ン に よ る
1991年 の オ ゾ ン ホ ー ル 観 測 計 画 神 沢 博
1・ 近 藤 豊
2要旨：第
32次南極地域観測隊によって実施される三つのポーラー・パトロール・
バルーン
(PPB)実験のうちの一つとして，昭和墓地
(69°S,40°E)から
1991年
9月 に，南極オゾンホールとして知られる南極大陸上空のオゾン層の破壊現象を観測す るための気球が放球される．オゾン，ニアロゾル，温度のその場
(insitu)での観測 を，南極大陸上空
50hPa( 約
18km)を浮遊する気球の軌跡に沿って，約
10日間 行う．この観測の動機は以下の通りである：極域成層圏雲
(PSCs)は冷たい極域下 部成層圏で形成されるニアロゾルから成ること；冬の後期あるいほ春の初期のオゾ ンの減少（南極オゾンホールの一側面）が，
PSCs表面で起こる不均ー系化学反応 過程によると考えられていること．オゾン減少は
50hPaの高度で顕著であり，
PPB
ほこの高度を浮遊して， ラグランジュ型の観測を行うことができる．従って，
PPB
によるオゾン観測は， オゾンの化学的ソース／シンクの大きさを，ほかの型の 観測に比べてより直接的に測ることができるという利点を持つ．ニアロゾル観測器 は，ニアロゾルの粒径分布を，
0.4ーlOμmの間を
7分割して測るので，
PSCsの微 物理および化学についての詳細な情報を与える．デーク取得および気球位置決定ほ
ARGOSシステムを使用して行う．ゼロプレッシャ一気球の高度は，オートバラス
トシステムによってほぼ一定高度に維持される．
Abstract: Among the three Polar Patrol Balloon (PPB) experiments planned in the course of the 32nd Japanese Antarctic Research Expedition, one balloon will be launched from Syowa Station (69°S, 40°E) in September 1991 to observe deple‑ tion of the ozone layer over Antarctica—the so‑called Antarctic ozone hole. In situ measurements will be made of ozone, aerosol, and temperature along the track of the balloon around the 50 hPa level
(
18 km) for about 10 days. The motiva‑ tion for this exercise is as follows: Polar Stratospheric Clouds (PSCs) consist of aerosols which are formed in the cold polar lower stratosphere; the decrease of ozone in the Antarctic lower stratosphere in late winter and early spring, which is an aspect of the Antarctic ozone hole, is believed to be due to heterogeneous chemical processes occurring on the surface of PSCs. The PPB observation is a Lagrangian type observation, and it will be held around the 50 hPa level where the ozone decreases most. Consequently, the ozone concentration measurement has the advantage that it will be able to detect the in situ chemical budget of ozone more directly than other types of observation. The aerosol instrument measures aerosol concentrations in the diameter range of 0.4‑10 micron meters, devided into 7 classes to give detailed information on the microphysics and chemistry of PSCs. Data acquisition and balloon positioning will utilize the ARGOS system.1
国立極地研究所.
National Institute of Polar Research, 9—10, Kaga 1‑chome, Itabashi‑ku, Tokyo173.
2
名古屋大学太陽地球環境研究所.
Solar‑Terrestrial Environment Laboratory, Nagoya University, 13, Honohara 3‑chome, Toyokawa 442.南極資料，
Vol.35, No. 2, 227‑237, 1991Nankyoku Shiry6 (Antarctic Record), Vol. 35, No. 2, 227‑237, 1991
228 Hiroshi KANZAWA and Yutaka KONDO
The almost constant altitude of the zero‑pressure balloon will be regulated with the help of an auto‑ballast system.
1. Introduction
The Polar Patrol Balloon (hereafter ref erred to as PPB) project is to execute a long duration circumpolar balloon experiment in the Antarctic using a zero‑pressure balloon with an auto‑ballast control to keep the balloon at an almost constant pressure level in the stratosphere. The PPB project aims at placing several moving stations at a balloon altitude during long periods (about 10‑20 days) over the Antarctic region for geophysical and astrophysical observations. The concept and feasibility of the project has been reviewed by the Institute of Space and Astronautical Science (ISAS). The project was proposed by ISAS to the National Institute of Polar Research (NIPR) that is responsible for the annual Japanese Antarctic Research Expedition (JARE). Since 1984, NIPR, ISAS, and a nation‑wide network of collaborating scientists have carried out the PPB program, and balloon technology for the long duration flights has been developed (NISHIMURA et al., 1984; KODAMA and FUKUNISHI, 1984; NISHI‑ MURA et al., 1985; NAGATA et al., 1985). Two test flights launched from Syowa Station (69°S, 40°E) were carried out by the 28th Japanese Antarctic Research Expedition (JARE‑28) in 1987 (MIYAOKA et al., 1988), and a test flight was carried out by JARE‑30 in 1990 (KADOKURA et al., 1991). These test flights carried out during two austral summers have convinced us that PPB will be a good tool for scientific observations (e.g., EJIRI et al., 1990).
On the basis of the foregoing developments described above, scientific observa‑ tions using the PPB have been planned (FUJII et al., 1989; EJIRI et al., 1990). Three PPB experiments had been planned for JARE‑32; one of these is devoted to observa‑ tion of the Antarctic ozone hole, i.e., in situ measurements of ozone, aerosol, and temperature around the 50 hPa (about 18 km) level. The present paper describes the plan of the ozone hole observation using the PPB scheduled for September 1991. Two earlier PPB flights, for auroral observations, were incorporated in JARE‑32:
Successfully carried out already in December 1990‑J anuary 1991, their results are being reported on elsewhere by other authors.
2. Participants of the Ozone Hole PPB Project
A team of eleven persons, including ourselves, is involved in the plan of the ozone hole PPB observation. Some are responsible for carrying out the experiment at Syowa Station, others will analyze the resulting data. The role division of the par‑ ticipants is as follows:
KANZA w A, Hiroshi (National Institute of Polar Research): Management of the ozone hole PPB experiment as a whole; Feasibility study of the PPB experiment from a meteorological perspective; Investigation of the significance of atmo‑ spheric dynamics.
KONDO, Yutaka (Solar‑Terrestrial Environment Laboratory, Nagoya University): Management of the ozone hole PPB experiment as a whole; Development of the observational instruments for ozone and aerosol measurements; Investigation
